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ECU / Injector issue or am I over thinking

natiAR230

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New 2007 AR230 owner, this forum has a been an amazing resource and wanted to ask a few question to see what others thought of an issue I possibly may be having. So I recently changed the plugs and oil, the oil was a little over filled in both engines but was not in the air filter. I did notice a smell of gas from the oil which I know is not normal. I haven't had any issues and have been monitoring the oil level the past week and haven't noticed any significant changes, but there is a faint smell of gas in the new oil. A few questions.

1. Is it normal to have some gas go into the oil from running at idle? Or possibly from rings (engine has 250hrs)
2. What are the chances I would be having the same issue on both engines at the same time (gas smell is in both oil)
3. I ordered Yamaha ring free additive to run through and see if it helps at all and other additives I should try?
4. Should I be looking for any symptoms of a bad ECU or bad injector?

The engines have been running fine 10k rpms and about 50 mph. Being new to the boat I don't know if it has been using any additional gas. Any help or ideas is appreciated.
 
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Julian

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natiAR230

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@bronze_10 can tell you about his experience, but from what I've read when you have a bad ECU/stuck injector, you don't just smell gas....your oil fills with gas and overflows.
Yeah that's what I am afraid of, plus since I seem to smell it in both engines is even worse. @bronze_10 any insight you have would be appreciated
 

Scottintexas

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I would be cautious, it's rare we see an ECU go bad and it's usually a water exposure issue, now you think both engines may have an issue,

I would take it out an run it and monitor the oil level closely, if the oil levels continues to increase then you definitely may have an issue to address,

In the meantime you may take the cover off the ECU box and see if there are any signs of water intrusion to make you more concerned,

You should also buy a YDS to help you monitor your engines,

See the link in my signature below for known issues with your year boat, especially the scupper valve,



.
 

bronze_10

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With mine the number one injector stuck approximately 80% open. I gauged this by the fact the engine would not go full throttle.. It would slowly go over 10k and then back down to sonewhere in the 8's. When it was at idle u could clearly see gas in the water behind the boat. And the engine didn't want to start as easily as it typically does. You could also smell gas too. If I could have stopped there and not ran the engine anymore it would have not really been an issue. But it happened in bimini and I had to get the boat back. So I ran the engine at near 8k for the 60 ish miles back to florida. I turned it off when I came into the no wake area.

Once at home I drained the oil from the bottom of the motor. It is an absolute pain but you can do it. If you don't drain the oil that way you will continue to have contaminated oil in your engine. Removing the oil out of the rear oil tank only gets maybe half of it out. I removed 9 quarts of fuel contaminated oil from an engine that hold 4.5 quarts. It had that much fuel in it but still ran.

I opened the box that contains the ecu in it and it had a large amount of water in it. I sent that ecu off to be repaired and I am waiting to hear back. I used the ecu from the other engine (the box also had water in it but no where near as much) and installed it in the engine with the stuck injector in order to flush the salt water out and ciculate the good oil through the engine. The engine ran fine with that ecu so I am convinced at this point the ecu was my problem.

As for both engines having fuel contamination that is a bit more interesting. My engine did not run at full RPM and it was obvious something was not right.

Other more mechanically enclinded members like @veedubtek or @PaulyB may be able to yell you more but I would think if the rings were that bad it would burn oil more than fuel would leak around them.

Yours could be an intermitant injector issue at low RPM and works fine at higher RPM.

If I were u I would start by draining the oil out of the bottom of the motor. Make sure u get all contaminated oil out.. Then refill and replace the spark plugs.

Then at least you know the oil and engine is good. Then keep checking the levels and gas smell.

You purchased a used boat.. There is no telling what someone did to it. There are boat people, then there are people with boats! Try to buy a used boat from boat people! Lol
 

natiAR230

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I would be cautious, it's rare we see an ECU go bad and it's usually a water exposure issue, now you think both engines may have an issue,

I would take it out an run it and monitor the oil level closely, if the oil levels continues to increase then you definitely may have an issue to address,

In the meantime you may take the cover off the ECU box and see if there are any signs of water intrusion to make you more concerned,

You should also buy a YDS to help you monitor your engines,

See the link in my signature below for known issues with your year boat, especially the scupper valve,



.
Thanks for the input - I did replace the scupper valve flap at the beginning of the season. Is the cover of the ECU pretty easy to get off? It's the black box on the back wall correct?
 

natiAR230

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With mine the number one injector stuck approximately 80% open. I gauged this by the fact the engine would not go full throttle.. It would slowly go over 10k and then back down to sonewhere in the 8's. When it was at idle u could clearly see gas in the water behind the boat. And the engine didn't want to start as easily as it typically does. You could also smell gas too. If I could have stopped there and not ran the engine anymore it would have not really been an issue. But it happened in bimini and I had to get the boat back. So I ran the engine at near 8k for the 60 ish miles back to florida. I turned it off when I came into the no wake area.

Once at home I drained the oil from the bottom of the motor. It is an absolute pain but you can do it. If you don't drain the oil that way you will continue to have contaminated oil in your engine. Removing the oil out of the rear oil tank only gets maybe half of it out. I removed 9 quarts of fuel contaminated oil from an engine that hold 4.5 quarts. It had that much fuel in it but still ran.

I opened the box that contains the ecu in it and it had a large amount of water in it. I sent that ecu off to be repaired and I am waiting to hear back. I used the ecu from the other engine (the box also had water in it but no where near as much) and installed it in the engine with the stuck injector in order to flush the salt water out and ciculate the good oil through the engine. The engine ran fine with that ecu so I am convinced at this point the ecu was my problem.

As for both engines having fuel contamination that is a bit more interesting. My engine did not run at full RPM and it was obvious something was not right.

Other more mechanically enclinded members like @veedubtek or @PaulyB may be able to yell you more but I would think if the rings were that bad it would burn oil more than fuel would leak around them.

Yours could be an intermitant injector issue at low RPM and works fine at higher RPM.

If I were u I would start by draining the oil out of the bottom of the motor. Make sure u get all contaminated oil out.. Then refill and replace the spark plugs.

Then at least you know the oil and engine is good. Then keep checking the levels and gas smell.

You purchased a used boat.. There is no telling what someone did to it. There are boat people, then there are people with boats! Try to buy a used boat from boat people! Lol
Wow sorry to hear - So yeah I haven't had the RPM issues at all. I will keep an eye on the oil. The previous owner seemed very meticulous on maintenance from talking with him a few times. One thing that could have been a red flag is that the scupper flap was rotted and he kept the boat in the water during the season in fresh water for almost 2-3 months. I will be pulling the cover off the ECU's to check for water.
 

Scottintexas

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The scupper flap is not the issue, the weak plastic scupper itself can crack and let water in, you should replace the entire scupper with a stainless steel version,

The ECU is in the black box, look in the FAQ tab at the top of the page for DIY info,
 

bronze_10

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Thanks for the input - I did replace the scupper valve flap at the beginning of the season. Is the cover of the ECU pretty easy to get off? It's the black box on the back wall correct?
Yes.. Its held on with four bolts through the bulkhead.. Then like 20 screws to take off the back and look inside.

The scupper is a real problem on our boats. The plastic scupper gets brittle.. If the scupper it self breaks then you have a 2 inch hole under the waterline. Its bear to reach but it is important that it is changed.
 

bronze_10

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One more thing. My oil was thin and had a smell but it wasn't overly gas strong. It was definitely gas but not as strong a smell as I imagined.
 

natiAR230

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With mine the number one injector stuck approximately 80% open. I gauged this by the fact the engine would not go full throttle.. It would slowly go over 10k and then back down to sonewhere in the 8's. When it was at idle u could clearly see gas in the water behind the boat. And the engine didn't want to start as easily as it typically does. You could also smell gas too. If I could have stopped there and not ran the engine anymore it would have not really been an issue. But it happened in bimini and I had to get the boat back. So I ran the engine at near 8k for the 60 ish miles back to florida. I turned it off when I came into the no wake area.

Once at home I drained the oil from the bottom of the motor. It is an absolute pain but you can do it. If you don't drain the oil that way you will continue to have contaminated oil in your engine. Removing the oil out of the rear oil tank only gets maybe half of it out. I removed 9 quarts of fuel contaminated oil from an engine that hold 4.5 quarts. It had that much fuel in it but still ran.

I opened the box that contains the ecu in it and it had a large amount of water in it. I sent that ecu off to be repaired and I am waiting to hear back. I used the ecu from the other engine (the box also had water in it but no where near as much) and installed it in the engine with the stuck injector in order to flush the salt water out and ciculate the good oil through the engine. The engine ran fine with that ecu so I am convinced at this point the ecu was my problem.

As for both engines having fuel contamination that is a bit more interesting. My engine did not run at full RPM and it was obvious something was not right.

Other more mechanically enclinded members like @veedubtek or @PaulyB may be able to yell you more but I would think if the rings were that bad it would burn oil more than fuel would leak around them.

Yours could be an intermitant injector issue at low RPM and works fine at higher RPM.

If I were u I would start by draining the oil out of the bottom of the motor. Make sure u get all contaminated oil out.. Then refill and replace the spark plugs.

Then at least you know the oil and engine is good. Then keep checking the levels and gas smell.

You purchased a used boat.. There is no telling what someone did to it. There are boat people, then there are people with boats! Try to buy a used boat from boat people! Lol
When you removed the ECU cover did you have to go through the rear access to get the 4 bolts out. Or did you see water opening the small access cover on the front of the ECU?
 

natiAR230

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So last night I took both ECU covers off and didn't see any water damage or standing water or moisture. I ended buying some Yamaha ring free and put in my gas and ran the boat almost two hours last night. Ran great and checked the oil level throughout the night and didn't see any change in the oil level. I also noticed that the gas smell is more prominent when the engine is cold and didn't notice the smell when I was the engine was warm. I guess it could be bc the gas in the oil would rise to the top and when the engine hasn't been started it would be sitting near the top where the dipstick is? I was wondering if anyone had any additional insight? I think I'm going to pull a quart of oil out of each engine when cold and replace with new oil - with the though of pull the gas off the top and then run and check again? thanks for the insight guys!
 

Scottintexas

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how difficult / time consuming was it to take the covers off ?

I think removing more oil wouldn't hurt but if you think you had gas in there the full drain would be the most preventative measure and what I would do, you might pull a quart out and put it in a glass jar to see if it separates.

I wonder if leaving the oil cap loose/off would let the gasoline evaporate or if it's in such a slurry it wouldn't ??
 

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I would think a little gas would eventually evaporate with operating temperatures, same as a little moisture.

If everything looks good, run it like you stole it, and check again later.

Maybe over the winter get the injectors tested and cleaned if you still have a desire to do more about it.

There is a breather that allows some air in (and oil out if it's too high) that should allow the evaporation even with the cooler cap on.
 
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natiAR230

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how difficult / time consuming was it to take the covers off ?

I think removing more oil wouldn't hurt but if you think you had gas in there the full drain would be the most preventative measure and what I would do, you might pull a quart out and put it in a glass jar to see if it separates.

I wonder if leaving the oil cap loose/off would let the gasoline evaporate or if it's in such a slurry it wouldn't ??
The ECU covers were way harder than I anticipated getting off - I wasn't anticipating take the whole back part off to reach the backs of the bolts for the ecu - a huge pain especially when you are by yourself, and I'm a novice mechanic at best. Not a bad idea on leaving the caps off I may give that a shot.
 

natiAR230

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I would think a little gas would eventually evaporate with operating temperatures, same as a little moisture.

If everything looks good, run it like you stole it, and check again later.

Maybe over the winter get the injectors tested and cleaned if you still have a desire to do more about it.

There is a breather that allows some air in (and oil out if it's too high) that should allow the evaporation even with the cooler cap on.
That's my plan tonight - to run through the other half of the gas with the Ring Free and run it hard. Hopefully this minimally gets me through the rest of the season and I can look back into it this winter.
 

bronze_10

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how difficult / time consuming was it to take the covers off ?

I think removing more oil wouldn't hurt but if you think you had gas in there the full drain would be the most preventative measure and what I would do, you might pull a quart out and put it in a glass jar to see if it separates.

I wonder if leaving the oil cap loose/off would let the gasoline evaporate or if it's in such a slurry it wouldn't ??
The first one was a pain in the ass... When I took the ecu off of the other side to check my good engine I hotnit off in about 30 min.. My wife helped on getting the main 4 bolts off... And back on..
 

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I’ve got a great one for you all. Same issues on my ‘05 ar230ho with rpms dropping on port motor. Would drop to 8k rpm then back up to 9k and repeat. At one point when the rpm dropped I happened to push the bow up button on my port trim tab and the rpm kicked back up to 9k. Every time the rpm would drop down (cylinder not firing, gas dumping into oil) I’d hit that bow up button again and it would all fire correctly again. What the heck could be going on here to cause this is?
 

Beachbummer

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Voltage regulator going nuts? Only correlation I can imagine between those 2 things
 
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